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In this paper, first, a new criterion, titled “surplus percent of the customers” is defined for static transmission expansion planning in restructured power systems. Then by a simple example, the new criterion is compared with some already presented market-based criteria and it is shown that the new criterion can realistically evaluate the transmission network expansion from the market view. In this paper the bid of market participants (producers and consumers) to sell and buy power are considered as random variables with known probability density functions. Then the expectation of the surplus percent is introduced as an index for measuring the competitiveness of each transmission expansion plan. Then a least-investment cost expansion plan that increases the surplus percent to its ideal or near ideal value is searched. In this paper a fast method is also presented to calculate the expectation of the surplus percent using Monte-Carlo simulation with a predefined approximation. The results of applying the proposed method are illustrated for an example 8-bus power system.

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In this paper, the anti-plane stress analysis in an infinite elastic plane with multiple cracks is carried out by using the distributed dislocation technique. The solution is obtained for an infinite plane containing the screw dislocation via Fourier transform of biharmonic equation for the analysis of infinite plane in gradient elasticity. These solutions are used to perform integral equations for an infinite plane weakened by multiple straight cracks. Integral equations are hypersingular type which are solved numerically for density of dislocation on the cracks surfaces. The numerical method in Chebyshev series form are used to solve the hypersingular integral equations. The solution of integral equations leads to dislocation density functions. The stress intensity factor for cracks tips are formulated in terms of density of dislocation. Employing the definition of dislocation density, stress intensity factors for cracks tips are calculated. The influence of size-effect and crack location on the stress intensity factors are studied. To confirm the validity of formulations, numerical values of stress intensity factors are compared with the results in the literature. The results of the present approach are in excellent agreement with those in the literature. Some new examples with different geometrics of cracks are solved to illustrate the applicability of procedure.

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In a structural analysis, dynamic response of a crack is of significant importance as well as the impacts of elastic waves on stress intensity factors (SIF). In this paper, dynamic analyses of multiple cracks on a half-plane subjected to anti-plane shear stresses are presented. Stress intensity factors are calculated and the interaction of elastic waves with the boundary of plane and the cracks' tips is investigated at different locations. The distribution discontinuous displacement techniques are used, enabling us to solve the crack problems in dynamic fracture mechanics. Integral transformations (Laplace and Fourier) are applied to elastodynamics equations and by using a set of appropriate boundary conditions solved discontinuous displacement and the crack problem is solved through discontinuous displacement method. As a result, the stress equations with hypersingularity terms are obtained. Using Chebyshev series expansion and collocation points in Laplace domain, the crack solution is achieved. Finally, different algorithms of numerical Laplace inversion are presented and the stress intensity factors (SIF) are obtained. The presented results are compared with published data and a good agreement is observed. Moreover, it is also demonstrated that the present theoretical study is capable of modelling multiple cracks with different arrangements.

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Tanks in water distribution networks are used to store water for emergency conditions, fire flow demand and demand oscillations controll. Construction of tanks spends a lot of money and therefore using whole volume of tanks is essential while operation. Otherwise, if tank volume will be more or less than what is required during operation, tank reliability is reduced. Accordingly, in this paper, a new relationship for tank reliability according to water level variation in tanks is defined. Therefore, maximum water level in tanks is defined as the decision variable. The definition of tank reliability is as follows. At first, the values of maximum level for each tank is computed such a way that optimal use is provided from balancing volume of tanks. In fact, for these maximum level values, maximum reliability is acheived for each tank. Now if during optimization process, a value lower than these computed maximum level is selected for decision variables, tank reliability is reduced. To compute the value of tank reliability, the values of tank water level for the selected decision variables is devided by the values of tank water level for maximum tank reliability. Also, because water level variation can effect on pressure and water age in demand nodes, this effect is investigated by considering hydraulic and quality reliability. In fact, variation of water level in tanks changes node demand pressures and in result actual node demands. Also, variation of water level or on the other hand variation of storage volume affects on water age in demand nodes. Besides, in order to investigate the simultaneous effect of water level variation on hydraulic and quality reliability, a relationship is also defined for integrated reliability. Definition of integrated reliability is to investigate whether there is optimum maximum tank level values that both hydraulic and quality reliability is improved simultaneusly while tank construction costs is minimum. Optimal management of tanks in water distribution networks to provide required water of consumers with desired quality is of high importance. To acheive this, optimization is defined as a powerful tool. In this paper, by focusing on operation phase, multiobjective optimization of water distribution performance is performed in which tank costs is considered as the first objective and tank reliability, node hydraulic reliability, node water age reliability and integrated reliability is considered as the second objective. Ant colony algorithm is codified in Microsoft Visual C++ for optimization due to its simplicity and high performance. The validity of the edited algorithm is tested on mathematical functions and proved to be applicable on water distribution networks. The created trade-off curve from multiobjective optimization helps the decision makers to select the top choice based on the importance of their own criterion whether it is hydraulic or quality.

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In this study, based on the third-order shear deformation theory the equations of motion are obtained to analyses the deformation of a long and slender composite beam. The beam has initial geometric imperfection and subjected to impact load. The impact procedures are applied by rigid body with a specific speed, off-center and at a certain distance from the beam's surface. Hamilton’s principle and the von-Karman nonlinear strain-displacement relationship are used to obtain the equations of motion that they are based on displacement and in a set of coupled nonlinear partial differential equations in dynamic mode. The generalized differential quadrature Method (GDQM) is used to discretize the obtained equations and convert them into a set of ordinary differential equations. Newton-Raphson iterative scheme is employed to solve the resulting system of nonlinear algebraic equations. Then, by solving the equations of the system, the effects of initial geometric imperfection on the beam’s deflection have been studied. Also the effects of mass and the initial velocity of the impactor on the beam’s deformation are investigated. The results of this research show that an increase in the amount of the initial velocity and mass of the impactor entail an increase in the beam deformation.

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Biologic tissues modeling play an important role in understanding the tissue behavior and development of synthetic materials for medical applications. It is also a vital action to develop the predictive models for a wide range of uses including medical and tissue engineering. Various strain energy functions have been introduced to model arteries to date. The newest introduced strain energy function is the Nolan strain energy function. Two-layer arterial modeling using this strain energy function has not been performed so far. In this paper, modeling the arteries was carried out in the form of double layers including media and adventitia and hyperelastic material assumption. At first, governing equations were driven based on continuum mechanics. Boundary conditions including inner pressure of artery, axial load and torque as well as static equilibrium were applied. Moreover, Cauchy stress components were gotten by using the continuum mechanics relations. Then, the equilibrium equations in cylindrical coordinate were obtained by using the Cauchy stress. Stress distribution through the artery wall was specified by solving the resulting nonlinear partial differential equations based on generalized differential quadrature method. In the beginning, the artery modeling was conducted in the form of monolayer including the media layer and the results were compared with experimental ones, comparison between stresses in the artery wall and experimental data showed that the volcanic energy function of Nolan is suitable for modeling. After that, the stress distribution was obtained by artery modeling in the form of double layers including the media and adventitia layers.

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The sugar beet crop has always been attacked by various pests and diseases. Rhizomania viral disease, which has spread in different regions of sugar beet cultivation, has become a disease of prime importance for the crop in the last three decades. Resistant cultivar usage is the only reliable way to manage rhizomania disease. In order to identify promising genotypes, eleven sugar beet genotypes with natural infection to rhizomania, in a company with three controls, were assessed in a Randomized Complete Block Design (RCBD) with four replications. The experiment was conducted in six research stations of Karaj, Khoy, Kermanshah, Mashhad, Miandoab, and Shiraz for two cropping seasons (2020 and 2021). Based on the rhizomania score, all genotypes had acceptable resistance to the disease. The Additive Main Effects and Multiplicative Interaction (AMMI) stability analysis illustrated that the first five principal components were significant and specified 88.8% of the total genotype by environment interaction variance. Gen-7, Gen-10, Gen-11, and Gen-2 were selected as stable genotypes based on the AMMI model. Genotype plus Genotype by Environment Interaction (GGE) biplot results also confirmed the superiority of Gen-10 and Gen-11 regarding sugar yield and stability in disease-infected environments. According to the results of the Multi-Trait Stability Index (MTSI), genotypes Gen-4, Gen-1, Gen-2, and Gen-11 were identified as stable genotypes under rhizomania-infected conditions. By applying different stability measurement methods, in addition to identifying the genotypes’ adaptation to different environments, accurate decisions for future breeding or cultivar registration can be achieved.